hehe, the less I spend on these forums the lerss I worry about my tyre pressure.
Having said that, I like the Marathon plus on my Birdy rear wheel to be 80psi or so, or it feels squirmy cornering. Big Apples around 40-50 or so. My contis go to 90 or 100.
Harshness has not been an issue for me (perhaps I have an iron bum).
All the above are approximate. I will keep riding until I discover the need for pumping. With the Schwalbe tubes, this is usually months at a stretch between pumping.